JP2006306453A - Aluminumless lid - Google Patents

Abstract

Provided is an aluminum-less cover material that has an appropriate soft texture but is excellent in shape retention when bent under a low load, has high surface impact strength, and does not easily crack when broken. .
SOLUTION: Styrene polymer (A) 20-87 mass%, soft olefin resin (B) 10-60 mass% having a melt flow rate of 5 g / 10 min or less at 230 ° C. and 21.2 N load, and , Aromatic vinyl-conjugated diene block copolymer and / or hydrogenated product thereof (C) 3-20% by mass [based on the total of 100% by mass of (A) to (C)], (B) is amorphous The olefin polymer (B1) 20-100% by mass and the crystalline olefin polymer (B2) 0-80% by mass [(B) 100% by mass standard], the amount of dispersed particle components in (A) And the conjugated diene polymer block in (C) and / or the hydrogenated product thereof is an aluminum comprising a thermoplastic resin having a total amount of 18% by mass or more [based on a total of 100% by mass of (A) and (C)] Less lid material.
[Selection figure] None

Description

  The present invention relates to an aluminum-less lid material that has an appropriate soft texture, has excellent shape retention when bent under a low load, has high surface impact strength, and is difficult to crack when broken. It is.

  Conventionally, aluminum foil is used as a material for lids to attach and seal food containers such as instant noodle containers, beverage containers, potion containers, etc. and containers made of synthetic resin filled with disposable medical supplies, etc. Are often used, and polystyrene-based resins and polypropylene-based resins are often used as containers. A lid member having an aluminum foil layer is used because it is excellent in stability at the time of sealing and peeling, and in a property of maintaining a bent state when the lid is opened (shape retention).

  However, recently, accidents in which foreign substances are mixed into processed food containers frequently occur, and safety measures are required. In a container that uses a lid with an aluminum foil layer, a metal detector cannot be used, so it will not be possible to detect metals such as nails, staples, blades that have not been molded, bolts / nuts, wires, springs, etc. . In addition, it has been reported that when an infant is swallowed directly with a tooth while drinking, a cut around the mouth occurs. Further, these containers need to be separately collected for the peeled aluminum foil and the container, and are inferior in recyclability.

As an alternative to such a conventional lid having an aluminum foil layer, a lid made entirely of plastic has been proposed. In Patent Document 1, a heat-resistant film is laminated on both sides of a base layer of a coextruded film in which a center layer made of high-density polyethylene and a polypropylene-based polymer and a coating layer made of high-density polyethylene are provided on both sides of the center layer. A lid material is disclosed in which a laminated material provided with a sealant layer on the lower surface of a laminated base material is punched into a predetermined shape. However, this plastic lid is applied only in the shape of only the flat portion, and is inferior in the ability to maintain the deformed state when deformed such as being bent. Patent Document 2 discloses a lid material using a copolymer obtained by copolymerizing ethylene and / or an α-olefin and a cyclic olefin or an alkenyl aromatic hydrocarbon. Although it is excellent in shape retention, the resin used is produced with a low polymerization capacity by using a substantially expensive catalyst system, so that it is expensive compared to conventional resins. Have
Japanese Patent Laid-Open No. 11-10810 JP 2001-294257 A

  An object of the present invention is to provide an aluminum-less lid material that has an appropriate soft texture but is excellent in shape retention when bent under a low load, has high surface impact strength, and is difficult to crack when broken. Is to provide.

  The present invention relates to a soft olefin resin (B) 10 to 60 having a melt flow rate (MFR) of 5 to 10 minutes or less at 20 to 87% by mass of a styrene polymer (A), 230 ° C., and 21.2 N load. And 3 to 20% by mass of an aromatic vinyl-conjugated diene block copolymer and / or a hydrogenated product (C) thereof [component (A), component (B) and component (C) Of 100% by mass in total], the soft olefin resin (B) comprises 20 to 100% by mass of the amorphous olefin polymer (B1) and 0 to 80% by mass of the crystalline olefin polymer (B2) [ Component (B) based on 100% by mass], the amount of dispersed particle components in the styrene polymer (A), and the conjugated diene in the aromatic vinyl-conjugated diene block copolymer and / or its hydrogenated product (C). Polymer block and / or Its total amount of the hydrogenated product is intended to provide a 18% by mass or more [Component (A) and total 100 wt% based component (C)] Aluminum less cover material made of a thermoplastic resin.

  The aluminum-less lid material of the present invention has an appropriate amount by combining a styrene polymer, a soft olefin resin having a specific structure, and an aromatic vinyl-conjugated diene block copolymer and / or a hydrogenated product thereof. It is possible to obtain an aluminum-less cover material that has a soft texture but is excellent in shape retention when bent under a low load, has high surface impact strength, and is difficult to crack when broken.

  The styrenic polymer (A) used in the present invention is composed of one or more polymers mainly composed of styrene monomer units. For example, polystyrene (GPPS), high impact polystyrene (HIPS), styrene-acrylonitrile copolymer (AS), styrene-acrylic acid copolymer (SAc), styrene-methacrylic acid copolymer (SMAc), styrene-methacrylic Methyl acid copolymer (MS), Styrene-maleic anhydride copolymer (SMAH), Acrylonitrile-butadiene-styrene copolymer (ABS), Acrylonitrile-ethylene-propylene-nonconjugated diene-styrene copolymer (AES) , Methyl methacrylate-butadiene-styrene copolymer (MBS) and the like can be used. Two or more of these may be used in combination. Among these, a rubber-modified styrene polymer is preferable from the viewpoint of processability, dispersibility of the soft olefin resin (B), and impact resistance, and impact polystyrene is particularly preferable.

  When the styrene polymer (A) is a rubber-modified styrene polymer such as impact-resistant polystyrene, the amount of the dispersed particle component in the component (A) is 15 on the basis of 100% by mass of the component (A). -40 mass% is preferable. If this quantity is 15 mass% or more, the dispersibility of soft olefin resin (B) can be maintained favorable. Moreover, if it is 40 mass% or less, the productivity of a styrene-type polymer (A) will be excellent. The average particle size of the dispersed particle component in component (A) is more preferably in the range of 2 to 8 μm. When the average particle size is in the range of 2 to 8 μm, the impact strength as the resin composition is improved. This average particle diameter is measured by the following method. A sample solution containing dispersed particles is prepared by dissolving a styrene polymer in methyl ethyl ketone so that the concentration is about 1% by mass. This sample solution is irradiated with laser light using a laser diffraction type particle size distribution analyzer (SALD1100, manufactured by Shimadzu Corporation), and images of the generated diffracted light and scattered light are detected. Calculate the size and quantity. The average particle size is a value using 50% of the particle size in the cumulative volume distribution.

  The melt flow rate (temperature 200 ° C., load 49 N) of the styrenic polymer (A) is preferably 0.5 to 30 g / 10 minutes, and more preferably 1 to 15 g / 10 minutes. The lower limit values of these ranges are significant in terms of improving the formability of the sheet as the aluminum-less lid material. Moreover, the upper limit of each said range is significant at the point etc. which maintain the dispersibility of soft olefin resin (B) favorably, and improve the moldability of the sheet | seat as an aluminum-less lid | cover material.

  The soft olefin resin (B) used in the present invention is 20 to 100% by mass (preferably 40 to 100% by mass, more preferably 70 to 100% by mass) of the amorphous olefin polymer (B1), and The crystalline olefin polymer (B2) is 0 to 80% by mass (preferably 0 to 60% by mass, more preferably 0 to 30% by mass). The lower limit value of the content of component (B1) and the upper limit value of the content of component (B2) in each of these ranges are significant in terms of improving the flexibility and impact resistance of the aluminumless lid material.

  The amorphous olefin polymer (B1) is a polymer containing olefin monomer units, and has a crystal melting peak calorific value at −100 to 200 ° C. in differential scanning calorimetry (DSC) of 10 J / g or less. It is more preferable that the melting peak calorie is not observed. About this crystal melting peak calorie | heat amount, it is obtained by implementing on the following conditions using a differential scanning calorimeter, for example, DSC220C by Seiko Denshi Kogyo. About 10 mg of the sample is heated from room temperature to 200 ° C. at a rate of temperature increase of 30 ° C./min, and held for 5 minutes after completion of the temperature increase. Next, the temperature is decreased from 200 ° C. to −100 ° C. at a rate of temperature decrease of 10 ° C./min, and held for 5 minutes after the temperature decrease is completed. Next, the temperature is increased from −100 ° C. to 200 ° C. at a rate of temperature increase of 10 ° C./min, and the crystal melting peak heat quantity is obtained from the peak area observed at that time.

  The content of the α-olefin monomer unit in the amorphous olefin polymer (B1) is preferably 30 mol% or more, based on 100 mol% of all monomer units in the component (B1), and 40 mol%. The above is more preferable, and 50 mol% or more is particularly preferable. The lower limit of these contents is significant in terms of heat resistance. Examples of the α-olefin include propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene and the like. Two or more of these may be used in combination. Among these, propylene, 1-butene and 1-hexene are preferable, and propylene and 1-butene are particularly preferable.

  The amorphous olefin polymer (B1) may contain a monomer unit other than the α-olefin. Examples of the monomer constituting such a monomer unit include ethylene, a polyene compound, a cyclic olefin, and a vinyl aromatic compound. The content of the monomer units is preferably 70 mol% or less, based on 100 mol% of all monomer units in the component (B1).

  Preferable specific examples of the amorphous olefin polymer (B1) include a propylene homopolymer, a propylene-ethylene copolymer, a copolymer of an α-olefin other than propylene and propylene, and an α-olefin other than propylene. Examples include a copolymer of propylene and ethylene. Two or more of these may be used in combination. Among these, a propylene homopolymer, a propylene-ethylene copolymer, a propylene-1-butene copolymer, a propylene-1-hexene copolymer, and a propylene-ethylene-1-butene copolymer are more preferable. A 1-butene copolymer and a propylene-ethylene-1-butene copolymer are very preferable.

  Examples of the crystalline olefin polymer (B2) include homopolymers and copolymers of olefin monomers, and a homopolymer and a copolymer may be used in combination. Examples of the olefin monomer include ethylene and α-olefin. Specific examples of the α-olefin include propylene, 1-butene, 1-pentene, 3-methyl-1-butene, 1-hexene, 4-methyl-1-pentene, 1-octene and the like. Two or more of these may be used in combination. In particular, the crystalline olefin polymer (B2) is preferably a propylene homopolymer or a copolymer of olefin other than propylene and propylene. Among these, a propylene homopolymer, a propylene-ethylene copolymer, a propylene-1-butene copolymer, and a propylene-ethylene-1-butene copolymer are more preferable.

  In the present invention, the amorphous olefin polymer (B1) and the crystalline olefin polymer (B2) are specifically -100 to 200 in differential scanning calorimetry (DSC) which is a physical property of the polymer. Differentiated by the crystal melting peak calorie at ° C. That is, the crystalline melting peak calorie of the amorphous olefin polymer (B1) is preferably 10 J / g or less, and the melting peak calorie is not observed, whereas the crystalline olefin polymer (B2) has a crystalline melting peak. The peak heat quantity is preferably 30 J / g or more, and more preferably 60 J / g.

  The melt flow rate (temperature 230 ° C., load 21.2 N) of the soft olefin resin (B) is 5 g / 10 min or less, preferably 3 g / 10 min or less, more preferably 0.5 to 2 g / 10. Minutes. The lower limits of the above ranges are significant in that the dispersibility of the soft olefin resin (B) is maintained well. Moreover, the upper limit value of each of the above ranges is significant in terms of maintaining shape retention after the aluminumless lid member is bent.

  The aromatic vinyl-conjugated diene block copolymer and / or hydrogenated product (C) thereof used in the present invention comprises, for example, an aromatic vinyl polymer block D and a conjugated diene polymer block E, and has a block structure. Are preferably (DE) n-D type or (DE) n type (n is an integer of 1 to 10). The content of the aromatic vinyl polymer block D in the component (C) is preferably 30 to 80% by mass and more preferably 50 to 70% by mass based on 100% by mass of the component (C). The lower limits of the above ranges are significant in terms of affinity with the styrene resin (A). Moreover, the upper limit value of each of the above ranges is significant in terms of affinity with the soft olefin resin (B).

  Examples of the aromatic vinyl monomer used in the aromatic vinyl-conjugated diene block copolymer and / or its hydrogenated product (C) include styrene, α-methylstyrene, p-methylstyrene, and t-butylstyrene. , Divinylbenzene, N, N-dimethyl-p-aminoethylstyrene, 2,4-dimethylstyrene, N, N-diethyl-p-aminoethylstyrene, vinylnaphthalene, vinylanthracene and the like. Two or more of these may be used in combination. Of these, styrene and α-methylstyrene are preferable.

  Examples of the conjugated diene monomer used in the aromatic vinyl-conjugated diene block copolymer and / or its hydrogenated product (C) include 1,3-butadiene, isoprene, 2,3-dimethyl-1,3. -Butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, 4,5-dimethyl-1,3-octadiene, chloroprene and the like. Two or more of these may be used in combination. Of these, 1,3-butadiene and isoprene are preferable.

  The aromatic vinyl-conjugated diene block copolymer and / or its hydrogenated product (C) is at least one functional group selected from an acid anhydride group, a carboxyl group, a hydroxyl group, an amino group, an isocyanate group, and an epoxy group. A functional group-modified copolymer containing a group may be used. A mixture of a modified copolymer and an unmodified copolymer can also be used.

  In the aromatic vinyl-conjugated diene block copolymer and / or its hydrogenated product (C), the hydrogenation rate of the unsaturated bond in the conjugated diene polymer block E is the monomer in the conjugated diene polymer block E. Based on 100 mol% of unit, 50 mol% or more is preferable, 80 mol% or more is more preferable, and 90 mol% or more is particularly preferable. The lower limit values of the above ranges are significant in terms of preventing the occurrence of unmelted crosslinked gel due to heat retention in the extruder and heat history during recycling.

  In the aluminumless lid material of the present invention, the content of the styrene polymer (A) is 20 to 87% by mass, where the total of the component (A), the component (B) and the component (C) is 100% by mass. , Preferably it is 35-75 mass%, More preferably, it is 40-70 mass%. The lower limits of the above ranges are significant in terms of improving the formability of the sheet as the aluminum-less lid material. Moreover, the upper limit of each said range is significant in the point etc. which improve the softness | flexibility and impact resistance of an aluminum-less cover material.

  In the aluminumless lid material of the present invention, the content of the soft olefin resin (B) is 10 to 60% by mass, where the total of the component (A), the component (B) and the component (C) is 100% by mass. , Preferably it is 20-50 mass%, More preferably, it is 25-40 mass%. The lower limits of the above ranges are significant in terms of improving the impact resistance of the aluminumless lid member. Moreover, the upper limit value of each of the above ranges is significant in terms of improving the formability and shape retention of the sheet as the aluminumless lid material.

  In the aluminumless lid of the present invention, the content of the aromatic vinyl-conjugated diene block copolymer and / or its hydrogenated product (C) is the sum of component (A), component (B) and component (C). The content is 3 to 20% by mass, preferably 5 to 15% by mass. The lower limits of the above ranges are significant in terms of improving the compatibilizing ability and impact resistance of the styrene polymer (A) and the soft olefin resin (B). Moreover, the upper limit of each said range is significant at the point etc. which reduce raw material cost, etc., maintaining sufficient compatibilizing improvement effect.

  In the aluminumless lid of the present invention, the amount of dispersed particle components in the styrene polymer (A) and the aromatic vinyl-conjugated are based on the total amount of 100% by mass of the component (A) and the component (C). The total amount of the conjugated diene polymer block and / or its hydrogenated product in the diene block copolymer and / or its hydrogenated product (C) is 18% by mass or more. The lower limit of 18% by mass of the total amount is significant in terms of the flexibility of the aluminum-less lid member, the impact resistance, the dispersibility of the soft olefin resin (B), and the like.

  In addition to the above-mentioned main components (A) to (C), the aluminum-less lid material of the present invention includes other resin components, for example, styrene-butadiene random co-polymer as necessary within the range not impairing the characteristics of the present invention. Polymer, hydrogenated styrene-butadiene random copolymer, acrylonitrile-butadiene copolymer, ethylene-propylene copolymer, ethylene-propylene-nonconjugated diene copolymer, ethylene-1-butene copolymer, ethylene -Methyl methacrylate copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, ethylene-vinyl acetate copolymer, ethylene ionomer, butyl rubber, chloroprene rubber, fluoro rubber, silicon rubber, urethane rubber, Rosin resin, polyterpene resin, synthetic petroleum resin, chroman resin, phenol System resin, xylene resin, cyclic olefin resin may be mixed with polylactic acid. If necessary, various additives such as antioxidants, heat stabilizers, processing stabilizers, ultraviolet absorbers, light stabilizers, anti-aging agents, lubricants, antistatic agents, rust preventives, fillers Plasticizers, mineral oils, silicone oils, flame retardants, flame retardant aids, antibacterial agents, colorants, dispersants, organic pigments, inorganic pigments, and the like may be blended.

  In order to obtain the aluminum-less lid material of the present invention, each raw material component is heated and melt-kneaded according to a known kneading technique in advance, and a method of obtaining a thermoplastic resin composition pellet once or directly mixing each raw material component into a molding machine The method of introducing what was done is mentioned. Specific examples for obtaining thermoplastic resin composition pellets include heat-kneading by a batch kneader such as a roll, kneader, Banbury mixer, etc., or a continuous kneader such as a single-screw extruder or a twin-screw kneading extruder Is mentioned.

  The aluminum-less cover material of the present invention can be obtained by molding the thermoplastic resin described above into a sheet shape. Examples of the molding method include T-die molding, inflation molding, calendar molding, and press molding.

  Although there is no restriction | limiting in particular as thickness of the aluminum-less cover material of this invention, It is preferable to set within the range of 0.1-2 mm.

  The aluminumless lid material of the present invention can be made into a laminate as long as the effect is not significantly impaired. In that case, the thermoplastic resin of this invention can be used for a surface layer or a base material layer according to each use. Examples of the layer other than the thermoplastic resin of the present invention include a sealant layer, a printing layer, a gas barrier layer, a heat-resistant protective layer, a light-shielding layer, and the like. Examples of materials used for these other layers include styrene resins such as GPPS, HIPS, AS, SAc, SMAc, MS, SMAH, ABS, AES, MBS, polyethylene, polypropylene, and ethylene-propylene copolymers. Polyolefin resins such as ethylene-propylene-butene copolymer, propylene-butene copolymer, ethylene-α-olefin copolymer, propylene-α-olefin copolymer, styrene-butadiene random copolymer, styrene-butadiene Random copolymer hydrogenated product, acrylonitrile-butadiene copolymer, ethylene-propylene-nonconjugated diene copolymer, ethylene-1-butene copolymer, ethylene-methyl methacrylate copolymer, ethylene-acrylic acid copolymer Polymer, ethylene-methacrylic acid copolymer, Ethylene-vinyl acetate copolymer, ethylene ionomer, nylon, polyethylene terephthalate, polybutylene terephthalate, polyvinylidene chloride, saponified ethylene-vinyl acetate copolymer, polylactic acid or inorganic / organic fine particles and fillers for these resins , Glass fiber, carbon fiber, vegetable fiber, paper, aluminum foil, and the like. Further, the form of these other layers is a sheet, a film, a foamed sheet, a stretched sheet, etc., and the joining method with these other layers is by using a plurality of extruders and a multilayer die, and using the aluminum-less material of the present invention. Multi-layer extrusion molding simultaneously with the lid material, or dry laminate molding or sandwich laminate molding using a two-component reactive adhesive etc. prepared separately from the aluminumless lid material made of the thermoplastic resin of the present invention Can be manufactured.

  The present invention will be described more specifically with reference to the following examples, which are illustrative only and are not intended to limit the present invention.

In the examples and comparative examples, the following components were used.
(A) Styrene polymer:
(A-1) Impact-resistant polystyrene (HIPS-1):
High-cis polybutadiene rubber (SV value: 0.06 Pa · s, 1,4-cis bond content: 98% by mass), which is a rubber-like polymer, is a raw material mixed solution in which 9.6% by mass is dissolved in 90.4% by mass of styrene. To 100 parts by mass, 5 parts by mass of ethylbenzene and 130 parts by mass of 1,1-bis (tertiary butyl peroxy) cyclohexane were added and dissolved to prepare a raw material solution.
This raw material liquid was continuously supplied at a supply rate of 14 L / hr to the first reactor, which was a complete mixing reactor (70 rotations / min) with an internal volume of 20 L, and polymerized at 130 ° C. Subsequently, the polymerization solution was continuously charged into the second and third reactors, which were plug flow reactors with an internal volume of 30 L and equipped with a stirrer, and polymerized. The polymerization temperature at the outlet of the second reactor and the polymerization temperature at the outlet of the third reactor were adjusted to 135 ° C. and 140 ° C., respectively. Subsequently, the polymerization liquid was continuously charged into a fourth reactor, which was a plug flow reactor having an internal volume of 30 L, and the outlet polymerization temperature was adjusted to 150 ° C., so that the polymerization conversion of styrene was 80 mass. Polymerization was allowed to proceed until%. After removing volatile components from this polymerization liquid at 240 ° C. under a reduced pressure of 0.5 kPa, liquid paraffin (viscosity at 40 ° C. = 7 × 10 ⁻⁵ m ² / s) with respect to 100 parts by mass of the resin. 2 parts by weight were added and pelletized.
In this way, high impact polystyrene (HIPS-1) having a dispersed particle component amount of 24% by mass, an average particle size of dispersed particle component of 4 μm, and MFR (temperature of 200 ° C., 49 N load) of 2.5 g / 10 min. Got.
(A-2) Impact-resistant polystyrene (HIPS-2):
Raw material mixed solution in which 5.2% by mass of low-cis polybutadiene rubber (SV value: 0.17 Pa · s, 1,4-cis bond content: 35% by mass), which is a rubbery polymer, is dissolved in 94.8% by mass of styrene With respect to 100 parts by mass, 5 parts by mass of ethylbenzene was added and dissolved to prepare a raw material solution.
This raw material liquid was continuously supplied at a supply rate of 14 L / hr to a first reactor which was a complete mixing reactor (120 rpm) having an internal volume of 20 L and polymerized at 135 ° C. Subsequently, the polymerization solution was continuously charged into the second and third reactors, which were plug flow reactors with an internal volume of 30 L and equipped with a stirrer, and polymerized. The polymerization temperature at the outlet of the second reactor and the polymerization temperature at the outlet of the third reactor were adjusted to 140 ° C. and 150 ° C., respectively. Next, the polymerization solution was continuously charged into a fourth reactor, which was a plug flow reactor having an internal volume of 30 L, and adjusted so that the outlet polymerization temperature was 160 ° C., and the polymerization conversion of styrene was 80 mass. Polymerization was allowed to proceed until%. After removing a volatile component from this polymerization solution under reduced pressure of 240 ° C. and 0.5 kPa, liquid paraffin (viscosity at 40 ° C. = 7 × 10 ⁻⁵ m ² / s) with respect to 100 parts by mass of the resin. 0 parts by weight were added and pelletized.
Thus, high impact polystyrene (HIPS-2) having a dispersed particle component amount of 18% by mass, an average particle size of the dispersed particle component of 3 μm, and an MFR (temperature of 200 ° C., 49 N load) of 3.0 g / 10 min. Got.
(A-3) Impact-resistant polystyrene (HIPS-3):
Raw material mixed solution in which 5.4% by mass of low-cis polybutadiene rubber (SV value: 0.17 Pa · s, 1,4-cis bond content: 35% by mass), which is a rubber-like polymer, is dissolved in 94.6% by mass of styrene. With respect to 100 parts by mass, 5 parts by mass of ethylbenzene was added and dissolved to prepare a raw material solution.
This raw material liquid was continuously supplied to a first reactor which was a fully mixed reactor (100 rotations / min) with an internal volume of 20 L at a supply rate of 14 L / hr and polymerized at 138 ° C. Subsequently, the polymerization solution was continuously charged into the second and third reactors, which were plug flow reactors with an internal volume of 30 L and equipped with a stirrer, and polymerized. The polymerization temperature at the outlet of the second reactor and the polymerization temperature at the outlet of the third reactor were adjusted to be 143 ° C. and 153 ° C., respectively. Next, the polymerization solution was continuously charged into a fourth reactor, which was a plug flow reactor having an internal volume of 30 L, and adjusted so that the outlet polymerization temperature was 163 ° C., and the polymerization conversion of styrene was 80 mass. Polymerization was allowed to proceed until%. After the volatile component was removed from this polymerization liquid under reduced pressure of 240 ° C. and 0.5 kPa, liquid paraffin (viscosity at 40 ° C. = 7 × 10 ⁻⁵ m ² / s) 0. 3 parts by weight were added and pelletized.
Thus, high impact polystyrene (HIPS-3) having a dispersed particle component amount of 20% by mass, an average particle size of dispersed particle component of 4 μm, and MFR (temperature of 200 ° C., 49 N load) of 3.5 g / 10 min. Got.
(A-4) Impact-resistant polystyrene (HIPS-4):
Raw material mixed solution in which 7.2 mass% of low-cis polybutadiene rubber (SV value: 0.17 Pa · s, 1,4-cis bond content: 35 mass%), which is a rubber-like polymer, is dissolved in 92.8 mass% of styrene With respect to 100 parts by mass, 5 parts by mass of ethylbenzene and 200 ppm by mass of tertiary lead decyl mercaptan (TDM) were added and dissolved to prepare a raw material solution.
This raw material liquid was continuously supplied at a supply rate of 14 L / hr to a first reactor which was a complete mixing reactor (internally 20 L) (50 rpm) and polymerized at 135 ° C. Subsequently, the polymerization solution was continuously charged into the second and third reactors, which were plug flow reactors with an internal volume of 30 L and equipped with a stirrer, and polymerized. The polymerization temperature at the outlet of the second reactor and the polymerization temperature at the outlet of the third reactor were adjusted to 140 ° C. and 150 ° C., respectively. Next, the polymerization solution was continuously charged into a fourth reactor, which was a plug flow reactor having an internal volume of 30 L, and adjusted so that the outlet polymerization temperature was 160 ° C., and the polymerization conversion of styrene was 80 mass. Polymerization was allowed to proceed until%. After removing the volatile component from this polymerization solution at 240 ° C. under a reduced pressure of 0.5 kPa, liquid paraffin (viscosity at 40 ° C. = 7 × 10 ⁻⁵ m ² / s) with respect to 100 parts by mass of the resin. 0 parts by weight were added and pelletized.
Thus, an impact-resistant polystyrene (HIPS-4) having a dispersed particle component amount of 29% by mass, an average particle size of the dispersed particle component of 8 μm, and an MFR (200 ° C., 49 N load) of 3.0 g / 10 min. Obtained.
(B) Soft olefin resin:
(B-1) Soft olefin resin (SOP-1):
Product name: Sumitomo Tough Selenium T1712 (specific gravity = 0.86, MFR (temperature 230 ° C., 21.2 N load) = 0.6 g / 10 min, amorphous olefin polymer / crystalline Olefin polymer mass ratio 85/15) was used.
(B-2) Soft olefin resin (SOP-2):
Product name: Sumitomo Tough Selenium T3712 (specific gravity = 0.86, MFR (temperature 230 ° C., 21.2 N load) = 3 g / 10 min, amorphous olefin polymer / crystalline olefin system) Polymer mass ratio 85/15) was used.
(B-3) Soft olefin resin (SOP-3):
Product name: Sumitomo Tough Selenium T5722 (specific gravity = 0.87, MFR (temperature 230 ° C., 21.2 N load) = 10 g / 10 min, amorphous olefin polymer / crystalline olefin system) Polymer mass ratio 70/30) was used.
(B-4) Ethylene-methyl methacrylate copolymer (EMMA):
Product name: Sumitomo Acrylift WM403 (specific gravity = 0.95, MFR (temperature 190 ° C., 21.2 N load) = 15 g / 10 min, MMA content = 38% by mass) manufactured by Sumitomo Chemical Co., Ltd. was used.
(B-5) Homopolypropylene (PP-1):
Product name: Sumitomo Mitsui Polypro E101G (specific gravity = 0.90, MFR (temperature 230 ° C., 21.2 N load) = 0.3 g / 10 min) manufactured by Sumitomo Mitsui Polyolefin Co., Ltd. was used.
(B-6) Random polypropylene (PP-2):
Product name: Sumitomo Nobrene FL6632G (specific gravity = 0.90, MFR (temperature 230 ° C., 21.2 N load) = 6 g / 10 minutes) manufactured by Sumitomo Chemical Co., Ltd. was used.
(C) Aromatic vinyl-conjugated diene block copolymer and / or hydrogenated product thereof:
(C-1) Styrene-ethylene-butene-styrene block copolymer (SEBS-1):
Product name: Dynalon 9901P (specific gravity = 0.97, MFR (temperature 230 ° C., 21.2 N load) = 3 g / 10 min, styrene content = 53 mass%, hydrogenated amount of conjugated diene = 47, manufactured by JSR Corporation Mass%) was used.
(C-2) Styrene-ethylene-butene-styrene block copolymer (SEBS-2):
Product name: Dynalon 8903P (specific gravity = 0.92, MFR (temperature 230 ° C., 21.2 N load) = 26 g / 10 min, styrene content = 35% by mass, amount of hydrogenated conjugated diene = 65, manufactured by JSR Corporation Mass%) was used.
(C-3) Styrene-butadiene-styrene block copolymer (SBS):
Product name: TR2000 (specific gravity = 0.96, MFR (temperature 190 ° C., 21.2 N load) = 3 g / 10 min, styrene content = 40 mass%, conjugated diene content = 60 mass%) manufactured by JSR Corporation. Using.

The physical properties in Examples and Comparative Examples were measured by the following methods.
(1) Sheet bending angle measurement:
A sheet having a thickness of 150 μm is manufactured by T-die sheet molding, cut into a length of 40 mm and a width of 40 mm, bent so that the sides parallel to each other overlap, and a load of 500 g (du Pont impact load) is applied to the crease. The folding angle of the sheet was measured when 60 seconds passed after 10 seconds from immediately after removing the load. The bending direction was performed for both MD and TD. As used herein, the bending angle is a protractor that measures the angle of the folded up sheet when the sheet angle before folding is 0 °.
(2) Sheet tension measurement:
A 150 μm thick sheet is produced by T-die sheet molding, and a JIS No. 1 dumbbell test piece is punched in the MD direction from the sheet using a punching die, and a distance between marked lines is 115 mm and a tensile speed is 200 mm using a tensile tester. The elastic modulus and fracture strain were measured under the conditions of / min and a temperature of 23 ° C.
(3) Drop weight impact energy measurement, fracture morphology observation:
A sheet having a thickness of 150 μm is manufactured by T-die sheet molding, cut into a length of 100 mm × a width of 100 mm, using a graphic impact tester manufactured by Toyo Seiki, a weight weight of 73.5 N, a drop height of 800 mm, a load amplifier 2K Unit, A test was performed under the conditions of a sampling time of 5 μsec, an input sensitivity of 10 V, and a temperature of 23 ° C., and the total falling impact energy was obtained from the obtained displacement-load waveform.
Moreover, the destruction state was observed and judged according to the following criteria.
“◎”: Complete punch-through type (there was a breakage of only a hole by a weight without causing a crack)
“○”: Penetration type (one with only one crack running from the hole by the weight)
“△”: Penetration type (with a crack from the hole due to the weight of 10 mm or more)
“×”: Half-penetration, half-crack type (Through-penetration type and crack propagation type are mixed)
"XX": Crack propagation type (there was no breakage due to weight propagation, no holes due to weight)

<Example 1>
60% by mass of high-impact polystyrene (HIPS-1) as the styrene polymer (A), 30% by mass of SOP-1 as the soft olefin resin (B), aromatic vinyl-conjugated diene block copolymer and / or Alternatively, SEBS-1 as a hydrogenated product (C) is blended at a ratio of 10% by mass, and EDI is added to Tanabe Plastics Machine's V65-S1000 type sheet forming apparatus (screw diameter 65 mmφ, L / D = 32). Using a 600mm ULTRAFLEX H100 die attached, a molten film was extruded under the conditions of a temperature of 230 ° C., a screw rotation speed of 20 rpm, and a T die lip opening of 1.0 mm, and the touch roll and cooling roll heated to 50 ° C. The sheet was shaped and the take-up speed was adjusted to obtain a sheet having a thickness of 150 μm. Various test pieces were cut out from the sheet and subjected to sheet bending measurement, tensile measurement, falling weight impact test, and hand cut test. The results are shown in Table 1.

<Example 2>
A sheet was prepared in the same manner as in Example 1 except that the styrene polymer (A) was changed to HIPS-2, and was similarly evaluated. The results are shown in Table 1.

<Example 3>
A sheet was prepared in the same manner as in Example 1 except that the styrene polymer (A) was changed to HIPS-3, and was similarly evaluated. The results are shown in Table 1.

<Example 4>
A sheet was prepared in the same manner as in Example 1 except that the styrene polymer (A) was changed to HIPS-4, and evaluated in the same manner. The results are shown in Table 1.

<Example 5>
A sheet was prepared in the same manner as in Example 2 except that the soft olefin resin (B) was changed to SOP-2, and evaluated in the same manner. The results are shown in Table 1.

<Example 6>
70% by mass of impact-resistant polystyrene (HIPS-2) as the styrene polymer (A), 20% by mass of SOP-1 as the soft olefin resin (B), aromatic vinyl-conjugated diene block copolymer and / or Or SEBS-1 was mix | blended in the ratio of 10 mass% as the hydrogenated substance (C), the sheet | seat was produced by the method similar to Example 1, and it evaluated similarly. The results are shown in Table 1.

<Example 7>
80% by mass of impact polystyrene (HIPS-2) as the styrene polymer (A), 10% by mass of SOP-1 as the soft olefin resin (B), aromatic vinyl-conjugated diene block copolymer and / or Or SEBS-1 was mix | blended in the ratio of 10 mass% as the hydrogenated substance (C), the sheet | seat was produced by the method similar to Example 1, and it evaluated similarly. The results are shown in Table 1.

<Comparative Example 1>
A sheet was produced in the same manner as in Example 1 using pellets containing 100 mass% of HIPS-1, and evaluated in the same manner. The results are shown in Table 1.

<Comparative Example 2>
60% by mass of HIPS-2 as styrene polymer (A), 30% by mass of EMMA as soft olefin resin (B), aromatic vinyl-conjugated diene block copolymer and / or hydrogenated product (C) SEBS-1 was blended at a ratio of 10% by mass, and a sheet was produced in the same manner as in Example 1 and evaluated in the same manner. The results are shown in Table 1.

<Comparative Example 3>
A sheet was prepared in the same manner as in Example 2 except that the soft olefin resin (B) was changed to PP-1, and evaluated in the same manner. The results are shown in Table 1.

<Comparative example 4>
Example 60% by weight of HIPS-3 as a styrenic polymer (A) and 40% by weight of SBS as an aromatic vinyl-conjugated diene block copolymer and / or its hydrogenated product (C) A sheet was prepared in the same manner as in No. 1 and evaluated in the same manner. The results are shown in Table 1.

<Comparative Example 5>
The same method as in Example 4 except that the soft olefin resin (B) was changed to SOP-3, and the aromatic vinyl-conjugated diene block copolymer and / or its hydrogenated product (C) was changed to SEBS-2. Sheets were prepared and evaluated in the same manner. The results are shown in Table 1.

<Comparative Example 6>
68% by mass of impact polystyrene (HIPS-3) as the styrene polymer (A), 30% by mass of SOP-1 as the soft olefin resin (B), aromatic vinyl-conjugated diene block copolymer and / or Or SEBS-1 was mix | blended in the ratio of 2 mass% as the hydrogenated substance (C), the sheet | seat was produced by the method similar to Example 1, and it evaluated similarly. The results are shown in Table 1.

<Comparative Example 7>
A sheet was prepared in the same manner as in Example 1 using 100% by mass of PP-2 pellets and evaluated in the same manner. The results are shown in Table 1.

  The aluminumless lid material of the present invention can be suitably used, for example, for instant noodles, rice cakes, cups, blisterback peel lids and the like by utilizing its excellent characteristics.

Claims (5)

Styrene polymer (A) 20 to 87% by mass, 230 ° C., soft olefin resin (B) 10 to 60% by mass with a melt flow rate (MFR) at 21.2N load of 5 g / 10 min or less, and , Aromatic vinyl-conjugated diene block copolymer and / or hydrogenated product (C) thereof 3 to 20% by mass [total of component (A), component (B) and component (C) 100 mass % Standard],
The soft olefin resin (B) comprises 20 to 100% by mass of the amorphous olefin polymer (B1) and 0 to 80% by mass of the crystalline olefin polymer (B2) [based on 100% by mass of component (B). ],
Amount of dispersed particle component in styrenic polymer (A) and conjugated diene polymer block and / or hydrogenated product thereof in aromatic vinyl-conjugated diene block copolymer and / or hydrogenated product (C) The aluminum-less cover material which consists of a thermoplastic resin whose total amount is 18 mass% or more [based on the total of 100 mass% of the component (A) and the component (C)].   The thermoplastic resin is 35 to 75% by mass of a styrene polymer (A), a soft olefin resin (B) 20 to 20 at 230 ° C. and a melt flow rate (MFR) at 21.2 N load of 5 g / 10 min or less. The aluminum-less cover material according to claim 1, comprising 50% by mass and 5 to 15% by mass of an aromatic vinyl-conjugated diene block copolymer and / or a hydrogenated product (C) thereof.   The thermoplastic resin is such that the styrene polymer (A) is impact-resistant polystyrene, the amount of dispersed particle components in the impact-resistant polystyrene is 15 to 40% by mass [based on component (A) 100% by mass], The aluminum-less cover material according to claim 1, wherein the dispersed particle component has an average particle diameter of 2 to 8 μm.   The aluminum-less cover material which uses the thermoplastic resin as described in any one of Claims 1 thru | or 3 as a base material layer.   The aluminum-less lid | cover material which uses the thermoplastic resin as described in any one of Claim 1 thru | or 3 as a surface layer.